COPD

Question 1

What causes airway narrowing/obstruction?

Answer 1

muscle spasm
mucosal oedema
airway collapse due to loss of support
tumour or foreign body stuck in lumen

Question 2

What are the 3 aspects that make up COPD?

Answer 2

chronic bronchitis
emphysema
small airway inflammation (respiratory bronchiolitis)

Question 3

Define chronic bronchitis.

Answer 3

Cough productive of sputum on most days for 3 months of at least 2 successive years

Question 4

How does chronic bronchitis come about?

Answer 4

Chronic irritation (cigarette smoke/atmospheric pollution) leads to a defensive increase in mucus production with increase in numbers of epithelial cells (esp. goblet cells). This gives a role in sputum production and increased tendency to infection

Question 5

Is chronic bronchitis reversible or non-reversible obstruction?

Answer 5

non-reversible

Question 6

What can cause small airway inflammation in COPD?

Answer 6

Goblet cell metaplasia, macrophage accumulation and fibrosis (scarring) around bronchioles may generate functional obstruction

Question 7

Define emphysema.

Answer 7

Increase beyond the normal in the size of the airspaces distal to the terminal bronchiole without fibrosis

Question 8

What types of emphysema are there?

Answer 8

centriacinar (centrilobular)
panacinar (whole lobule affected)
Other types can occur localised around scars in the lung

Question 9

How is emphysema diagnosed?

Answer 9

Difficult to diagnose

CT scan used - shows changes in lung density

Question 10

What is the “dilation” in emphysema due to?

Answer 10

loss of alveolar walls not an increase in normal space

Question 11

What can be found in the lungs of smokers and urban dwellers?

Answer 11

Carbon pigmentation

Question 12

How does emphysema impair respiratory function?

Answer 12

• diminished alveolar surface area for gas exchange

- loss of elastic recoil so support of small airways is not apparent leading to tendency to collapse with obstruction

Question 13

As COPD advances what does a decreased PaO2 lead to?

Answer 13

Dyspnoea and increased respiratory rate
Pulmonary vasoconstriction (and pulmonary hypertension)

Question 14

What are the 3 main epidemiological factors that relate to the development of COPD?

Answer 14

Smoking
atmospheric pollution
Genetic factors

Question 15

What is alpha1- anti-trypsin deficiency?

Answer 15

an autosomal dominant genetic condition
- deficiency in alpha1- anti-trypsin leads to an increased number of elastases (enzymes produced by neutrophils and macrophages) which leads to the destruction of elastic alveolar walls (emphysema)

Question 16

How does tobacco smoke indirectly inhibit alpha1- anti-trypsin?

Answer 16

Tobacco smoke Increases number of neutrophils and macrophages in lungand slows transit of these cells. This promotes neutrophil degranulation releasing elastase which inhibits  1 antitrypsin

Question 17

What leads to mucous hypersecretion in chronic bronchitis?

Answer 17

Marker hypertrophy of mucous secreting glands and hyperplasia of goblet cells (caused by chronic inflammation from cigarette smoke)

Question 18

In emphysema, which immune cells show a chronic inflammation?

Answer 18

neutrophils, macrophages and CD8+ T cells

Question 19

How is COPD assessed?

Answer 19

Symptoms
spirometry - degree of airflow limitation
CXR - to exclude aditional diagnoses
risk of exacerbations

Question 20

What are the symptoms of COPD?

Answer 20

chronic symptoms 
daily productive cough 
progressive breathlessness 
wheeze 
infective exacerbation - increased cough with purulent sputum

Question 21

What are the signs of COPD?

Answer 21

tachyponea
use of accessory muscles
hyperinflation of chest
decreased chest expansion

Question 22

what are emphysematous bullae?

Answer 22

Large (>1cm) closed off air spaces with trapped air seen on CXR

Question 23

How is the severity of COPD expressed?

Answer 23

Mild - FEV1 50-80% off predicted
Moderate - FEV1 30-49% predicted
Severe - FEV1 <30% of predicted

Question 24

What are the non-pharmacological interventions for COPD?

Answer 24

stop smoking 
encourage exercise 
treat poor nutrition or obesity 
influenza & pneumococcal vaccinations 
pul rehab/ palliative care

Question 25

How is Mild COPD treated?

Answer 25

Salbutamol or ipratropium

Question 26

How is moderate COPD treated?

Answer 26

Ipratropium or salmeterol and inhaled beclometasone (corticosteroid)

Question 27

How is severe COPD treated?

Answer 27

Salmeterol and beclometasone and ipratropium and refer to specialist

Question 28

What is the treatment for an acute exacerbation of COPD?

Answer 28

ABCDE 
IV access (FBC,U&Es, blood culture)
O2 (88-92%) & ABG 
Oral prednisolone/ IV hydrocortisone 
Amoxicillin oral (if infective)
Nebulised Salbutamol (bronchodilator)
Physiotherapy to expel secretions

Question 29

What are the complications of COPD?

Answer 29

Respiratory failure (type 2)
Cor pulmonale (heart failure 2y to disease of the lung)